1. Field of the Invention
The present invention relates to improvements in security post assemblies of the type used to block driveways, gateways, roads, car park entrances and the like, or as additional protection in front of windows or doors of business premises.
2. Description of the Related Art
In my U.S. Pat. No. 4,567,740 (European Patent Application No. 0,104,939) I have described and shown in FIGS. 14-17 a security post assembly comprising a base tube adapted to be sunk into the ground or other base, and a post which fits into the mouth of the tube, wherein a cover plate fixed to an arm hinged to the base tube is adapted to be swivelled with the arm between a covering position in which it covers the mouth of the tube and an upright position in which it stands beside a padlock housing secured to the post so that part of the arm enters a slot in the padlock housing and an aperture provided in that part of the arm engages the bolt of the padlock.
Although this security post assembly has been well received, there is also a demand for an assembly which offers the additional security of a mortise lock hidden within one of the components of the assembly.
British Patent Specification No. 2,125,084B describes a security post assembly in which a mortise lock is housed within the post in a position such that the lock bolt, when extended, protrudes through a wall of the post and engages a receiver in the base tube. However the lock bolt and the receiver in the base tube are both then located below ground level and are therefore subject to rust and corrosion. Furthermore the base tube described in GB No. 2,125,084B has a light weight removable cover plate which is easily lost or stolen and may then leave a dangerous hole in the ground when the mouth of the base tube is left uncovered. Alternatively a lightweight hinged cover could be used but such a cover can be easily damaged by vehicles and people may trip over it, when the security post has been removed.